Use of evidence-based therapies after discharge among elderly patients with acute myocardial infarction.
BACKGROUND
Postdischarge use of evidence-based drug therapies has been proposed as a measure of quality of care for myocardial infarction patients. We examined trends in the use of evidence-based drug therapies after discharge among elderly patients with myocardial infarction.


METHODS
We performed a cross-sectional study in a retrospective population-based cohort that was created using linked administrative databases. We included patients aged 65 years and older who were discharged from hospital with a diagnosis of myocardial infarction between Apr. 1, 1992, and Mar. 31, 2005. We determined the annual percentage of patients who filled a prescription for statins, beta-blockers and angiotensin-modifying drugs within 90 days after discharge.


RESULTS
The percentage of patients who filled a prescription for a beta-blocker increased from 42.6% in 1992 to 78.1% in 2005. The percentage of patients who filled a prescription for an angiotensin-modifying drug increased from 42.0% in 1992 to 78.4% in 2005. The percentage of patients who filled a prescription for a statin increased from 4.2% in 1992 to 79.2% in 2005. In 2005, about half of the hospitals had rates of use for each of these therapies that were less than 80%. The temporal rate of increase in statin use after discharge was slower among noncardiologists than among cardiologists (3.5%-2.8% slower). The rate of increase was 4.8% slower for among physicians with low volumes of myocardial infarction patients than among those with high volumes of such patients and was 5.7% greater at teaching hospitals compared with nonteaching hospitals.


CONCLUSIONS
Use of statins, beta-blockers and angiotensin-modifying drugs increased from 1992 to 2005. The rate of increase in the use of these medications after discharge varied across physician and hospital characteristics.
Austin
Peter C
PC
Institute for Clinical Evaluative Sciences, Toronto, Ont. peter.austin@ices.on.ca
Tu
Jack V
JV
Ko
Dennis T
DT
Alter
David A
DA
D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use*; D000368:Aged; D000369:Aged, 80 and over; D047228:Angiotensin II Type 1 Receptor Blockers / Q000627:therapeutic use*; D003430:Cross-Sectional Studies; D011307:Drug Prescriptions / Q000706:statistics & numerical data; D019317:Evidence-Based Medicine / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000188:drug therapy*; D010351:Patient Discharge / Q000639:trends*; D012189:Retrospective Studies; D016896:Treatment Outcome
D000319:Adrenergic beta-Antagonists; D047228:Angiotensin II Type 1 Receptor Blockers; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors